1. Field of the Invention
The invention relates to a data carrier with a data processing device as well as to an electronic component with a data processing device for such a data carrier.
2. Description of the Related Art
Recently doubts have arisen as regards the security of data carriers, it being claimed that security-relevant data can be discovered by observation of the power consumption of such a data carrier.
It is an object of the invention to ensure that such attempts cannot be successful.
This object is achieved according to the invention in that a data carrier with an external power supply is also provided with an internal power supply, at least one switching means being provided in the data carrier in order to realize temporary decoupling of the external power supply.
The advantage of the invention resides in the fact that the decoupling of the external power supply, preferably during security-relevant operations or at least partly during security-relevant operations of the data processing device, frustrates such attempts to fraud.
Advantageous embodiments of the invention are described in the dependent Claims.
The invention will be described in detail hereinafter.
Data carriers provided with data processing devices, for example so-called chip cards, incorporate a test function for the protection of security-relevant transactions, for example the dispensing of cash in money-dispensing machines; such a test function serves to test the authorization for the transaction. In order to establish proof of authorization, use is made of, for example so-called Personal Identification Numbers (PIN). The PIN can be tested in the data processing device of the data carrier while utilizing key algorithms. The power supply for the data carrier is customarily realized by way of contacts or by induction of alternating currents which are converted into a direct current in the data carrier.